return to home page Computational Chemistry Comparison and Benchmark DataBase Release 22 (May 2022) Standard Reference Database 101 National Institute of Standards and Technology
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Bad vibrational frequency predictions

19 02 11 15 45

Calculated frequencies that differ from experiment by more than 400 cm-1 or have a ratio with experiment outside of 0.7 to 1.2 are listed

Calculated vibrational frequencies ("theory" in table) are calculated at QCISD(T)/aug-cc-pVDZ
Calculated values were scaled by 0.9778.

Species Name mode int rot Symmetry Experiment Theory difference ratio
CH3OH Methyl alcohol 12 torsion A" 200 304 104 0.658
C2H6O2S Dimethyl sulfone 20 B1 262 184 -78 1.428
C2H4+ Ethylene cation 4 torsion Au 84 -288 -372 -0.292
C2H2 Acetylene 4 Πg 612 355 -257 1.722
C2H2+ acetylene cation 5 Πu 837 663 -174 1.262
HCN+ hydrogen cyanide cation 3 Π 760 2996 2236 0.254
CH3CCH propyne 10 E 328 245 -83 1.339
CHONH2 formamide 12 torsion A" 289 -42 -331 -6.905
CH3SCH3+ dimethyl sulfide cation 15 B1 172 136 -36 1.265
C6H4Cl2 1,2-dichlorobenzene 14 A2 695 512 -183 1.359
C6H4Cl2 1,2-dichlorobenzene 16 A2 152 123 -29 1.236
CH3CH2CH2CH3 Butane 5 Ag 1442 411 -1031 3.508
CH3CH2CH2CH3 Butane 8 Ag 1151 822 -329 1.400
CH3CH2CH2CH3 Butane 36 Bu 271 3021 2750 0.090
CH2BrCH2Cl 1-bromo-2-chloroethane 1 A' 2960 189 -2771 15.650
CH2BrCH2Cl 1-bromo-2-chloroethane 2 A' 2960 242 -2718 12.229
CH2BrCH2Cl 1-bromo-2-chloroethane 3 A' 1446 631 -815 2.292
CH2BrCH2Cl 1-bromo-2-chloroethane 4 A' 1444 720 -724 2.004
CH2BrCH2Cl 1-bromo-2-chloroethane 8 A' 726 1428 702 0.508
CH2BrCH2Cl 1-bromo-2-chloroethane 9 A' 630 1436 806 0.439
CH2BrCH2Cl 1-bromo-2-chloroethane 10 A' 251 3024 2773 0.083
CH2BrCH2Cl 1-bromo-2-chloroethane 11 A' 202 3033 2831 0.067
CH2BrCH2Cl 1-bromo-2-chloroethane 12 A" 3010 106 -2904 28.386
CH2BrCH2Cl 1-bromo-2-chloroethane 13 A" 3010 738 -2272 4.081
CH2BrCH2Cl 1-bromo-2-chloroethane 14 A" 1259 948 -311 1.327
CH2BrCH2Cl 1-bromo-2-chloroethane 17 A" 763 3087 2324 0.247
CH2BrCH2Cl 1-bromo-2-chloroethane 18 A" 123 3110 2987 0.040
C3H6O 2-Propen-1-ol 24 A 188 106 -82 1.772
CHSNH2 thioformamide 12 A" 393 269 -124 1.463
C5H8 Bicyclo[1.1.1]pentane 9 A2" 1220 3034 1815 0.402
C5H8 Bicyclo[1.1.1]pentane 9 A2" 832 1210 378 0.688
C5H8 Bicyclo[1.1.1]pentane 12 E' 1456 2968 1512 0.491
C5H8 Bicyclo[1.1.1]pentane 17 E' 540 873 333 0.618
C4H2 Diacetylene 7 Πg 482 -646 -1128 -0.746
C4H2 Diacetylene 8 Πu 630 487 -143 1.294
C4H2 Diacetylene 9 Πu 231 111 -120 2.073
CH2FCH2CH3 1-Fluoropropane 13 A' 1391 996 -395 1.397
F2CCCF2 tetrafluoroallene 5 B2 2052 687 -1365 2.985
F2CCCF2 tetrafluoroallene 6 B2 1030 545 -485 1.889
F2CCCF2 tetrafluoroallene 7 B2 581 371 -210 1.564
F2CCCF2 tetrafluoroallene 11 E 90 64 -26 1.410
CH2CCH2 allene 1 A1 3015 1043 -1972 2.890
CH2CCH2 allene 8 E 3086 1433 -1653 2.154
C3H6O Oxetane 12 A2 986 801 -185 1.231
C3H6O Oxetane 18 B1 90 -81 -171 -1.110
C3H6O Oxetane 23 B2 1228 984 -244 1.248
C3O2 Carbon suboxide 7 Πu 61 -126 -187 -0.484
HCNO fulminic acid 5 torsion Π 224 -251 -475 -0.892
CHBrCHBr Ethene, 1,2-dibromo-, (Z)- 8 B1 3079 650 -2429 4.736
HCCCl Chloroacetylene 5 Π 326 235 -91 1.388
P(CH3)3 trimethylphosphine 22 E 259 194 -65 1.336
C6H6 Benzvalene 10 A1 996 735 -261 1.355
H2CS- thioformaldehyde anion 4 B1 450 210 -240 2.146
CH2ClCCCl 1,3-dichloropropyne 14 A" 337 222 -115 1.520
SiF2+ Silicon difluoride cation 2 A1 350 275 -75 1.273
CFCl2 dichlorofluoromethyl radical 2 A' 747 608 -139 1.228
C2H- Ethynyl anion 3 Π 505 386 -119 1.307
C2H Ethynyl radical 3 torsion Π 372 42 -330 8.898
CH3 Methyl radical 2 torsion A2" 606 487 -120 1.246
CH2OH Hydroxymethyl radical 9 torsion A 234 420 186 0.557
HCCN cyanomethylene 5 Π 129 -492 -621 -0.262
CHCl2 dichloromethyl radical 4 A' 190 293 103 0.649
CH2Cl chloromethyl radical 4 B1 402 -162 -564 -2.477
BF3+ boron trifluoride cation 5 B2 1791 830 -961 2.158
NF3 Nitrogen trifluoride 1 A1 1032 607 -425 1.700
NF3 Nitrogen trifluoride 2 A1 647 980 333 0.660
NF3 Nitrogen trifluoride 3 E 907 462 -445 1.962
NF3 Nitrogen trifluoride 4 E 492 858 366 0.573
OClO- Chlorine dioxide anion 2 A1 418 305 -113 1.371
BCl3+ Boron Trichloride cation 3 E' 1104 628 -475 1.756
N2O4 Dinitrogen tetroxide 3 Ag 265 179 -86 1.478
N2O4 Dinitrogen tetroxide 4 torsion Au 82 144 62 0.569
N2O4 Dinitrogen tetroxide 9 B2u 265 90 -175 2.932
SF5 Sulfur pentafluoride 2 A1 633 479 -154 1.321
SF5 Sulfur pentafluoride 7 E 818 590 -228 1.386
SF5 Sulfur pentafluoride 9 E 387 310 -77 1.248
C3O Tricarbon monoxide 5 Π 109 -84 -193 -1.300
SiC2 Silicon dicarbide 3 B2 196 -184 -380 -1.067
C3 carbon trimer 3 Πu 63 -173 -237 -0.365
C4 Carbon tetramer 4 Πg 323 -230 -553 -1.407
C4 Carbon tetramer 5 Πu 160 -123 -283 -1.304
S3 Sulfur trimer 2 A1 281 535 254 0.525
SiH2D2 silane-d2 6 B1 2183 1578 -605 1.384
SiH2D2 silane-d2 8 B2 1601 2181 580 0.734
SF5Cl sulfur chloropentafluoride 11 E 273 897 624 0.304
HSSSH trisulfane 5 A' 240 192 -48 1.248
GeF Germanium monofluoride 1 Σ 809 626 -183 1.292
B4H10 Tetraborane(10) 10 A1 827 660 -167 1.252
B4H10 Tetraborane(10) 11 A1 785 547 -238 1.436
B4H10 Tetraborane(10) 12 A1 559 225 -334 2.489
B4H10 Tetraborane(10) 19 A2 662 393 -269 1.686
B4H10 Tetraborane(10) 36 B2 236 338 102 0.698
Cl3- trichloride anion 2 Σu 327 257 -70 1.273
BH3PH3 borane phosphine 12 E 447 361 -86 1.238
OPCl Phosphorus oxychloride 2 A' 308 463 155 0.666
OPCl Phosphorus oxychloride 3 A' 492 280 -212 1.760
H2OH2O water dimer 12 A" 88 129 41 0.685
H2POH Phosphinous acid 9 A" 375 250 -126 1.503
Mg2 Magnesium diatomic 1 Σg 48 24 -24 1.995
ClOF3 Chlorine trifluoride oxide 9 A" 412 335 -77 1.231
CHFCl Chlorofluoromethyl radical 6 A 540 390 -150 1.385
H2CNCN cyanamide, methylene 3 A' 2208 3012 804 0.733
H2CNCN cyanamide, methylene 4 A' 1621 2154 533 0.753
C2H3NO Nitrosoethylene 11 A' 490 332 -158 1.474
SNO Nitrogen oxide sulfide 1 A' 1527 488 -1039 3.129
ONNO NO dimer 3 A1 135 207 72 0.651
ONNO NO dimer 4 torsion A2 117 203 86 0.576
AlNC Aluminum isocyanide 3 Π 100 72 -28 1.391